M42 - Orion Nebula

[Robbie]

It's not too pretty - the background is very messy and there was awful horizontal banding in the dim areas. It was the first light for my modded 40D, and I took darks instead of ICNR.
So the horizontal banding and horrible background could've been any number of things including the camera, the USB, the power, the darks, the flats.
I was able to remove most of it with a Noel Carboni action.

I'll need to re-stack without darks, look at the raw lights etc, to try and figure out where they are. I had a horrible time guiding as usual, too.

I'm fairly happy with the nebula itself, but overall the image is pretty messy. I'm also not really sure why the modded camera didn't capture more of the dim browny/dusty areas. With 50 minutes of data @ISO800 I would've expected to capture more with the modded 40D.

!

ED80 + modded 40D on EQ6. 10x 5 minute lights @ ISO800, 10x 100s, plus 10x30s for the core layers.

1200px higher-res here (500kb):
Orion - M42

Thanks for looking. Suggestions welcome.[/QUOTE]

Yes you are right Mike this is a hideous amateurish photo and you really do need to lift your game because you are slipping!!!!!

[Paul Haese]

Mike just check for RF type interference from your cables. I found that bundling the power cables together and the download cables separately pretty much removed this problem with the banding when I was doing DSLR images.

I like the sharpness of the image and guiding looks good, but I am not 100% keen on the colour. When I have viewed this through Tims 22 I saw some hints of green in this nebula. The colour is also verified by the lack of orange stars in your image. There are some there and use these as your guide for colour balance. Usually I find if your stars are the right colours and saturation the rest of the image looks right too.

There is also some faint nebulosity in this image that I can just see with my overly bright screen, but pushing that out might cause the banding and diagonal noise to really leap out.

Good image all the same, especially given you have not imaged it for a while. However, time you did another object though. How many times have you imaged this now?`

[iceman (Mike)]

Thanks Paul. I thought about the interference too and will check for that next time.

I also agree with the colour - it came out very blue and i'm not sure if it's the white balance settings on this modded camera. I'll check the colour temperature and maybe re-stack. I did notice the lack of orange stars, especially compared to my last image of M42 which was over 1.5 years ago.

Yes - it's been 1.5 years since I imaged this nebula so I thought it was time for it again The last time was before IISAC2008 in October 2008..

Thanks again.